Migrate Self-managed PostgreSQL: Multi-tenant relational data

Summary

Move PostgreSQL data from Self-managed PostgreSQL to Ample, one component at a time. Destination verified on Ample: a tenant column on every row and query, with a cross-tenant read returning nothing (tenant_isolation=ok). Source procedure: Take a logical backup with pg_dump -Fc as a role that can read all application objects. Not migrated automatically: Custom extensions, tablespaces, replication topology, superuser-only settings and OS-level backups have no equivalent on the managed database. Cutover: Freeze writes with the user's go-ahead, take the final dump, restore, validate, redeploy with the managed DATABASE_URL, keep the source server until confirmed. Rollback: keep the source untouched until you confirm; nothing at the source is changed or deleted by this guide.

Infrastructure requirements

• Postgres: verified (Managed PostgreSQL 16 runs in its own microVM and is auto-provisioned when an app needs a database and no DATABASE_URL is supplied.)

Prerequisites

• Authorized access to the Self-managed PostgreSQL source and its export tooling
• An inventory of every component in scope and out of scope
• A validated backup or copy before any cutover
• An Ample account token with servers:write, databases:read

Exact tested configuration

• template: node-22
• runtime: node
• size: s-1vcpu-1gb
• install: npm install
• build: npm run build --if-present
• start: npm run start

Steps

1. Inventory the source. List what Self-managed PostgreSQL provides beyond the component you are moving. Out of scope here: Custom extensions, tablespaces, replication topology, superuser-only settings and OS-level backups have no equivalent on the managed database.
2. Source step 1. Take a logical backup with pg_dump -Fc as a role that can read all application objects.
3. Source step 2. Check the major version, installed extensions, tablespaces and custom roles against the managed engine (PostgreSQL 16, no custom extensions verified).
4. Source step 3. Restore into a scratch managed database first and compare row counts.
5. Provision and restore. Deploy the app once so a managed PostgreSQL 16 database exists (or create one with ample database create --engine postgres), then restore the dump with pg_restore using its connection string; keep migrations idempotent.

   ample database create --name <db-name> --engine postgres

6. Validate before cutover. Run the app's own checks and, for data, compare counts and checksums; the example checks are the pattern self-tests (/p/multi-tenant-relational-data).
7. Cut over. Freeze writes with the user's go-ahead, take the final dump, restore, validate, redeploy with the managed DATABASE_URL, keep the source server until confirmed.
8. Rollback. Point DNS or configuration back to the source. The source was never modified; deletion is a separate, user-executed step after validation.

Tested examples

• Express pattern fixture (destination) (tests/deploy-canaries/express-patterns): Verified destination basis: multi-tenant relational data.

Success checks

• destination app responds on its public URL (/ on the live URL, expect ample canary express patterns)
• multi-tenant-relational-data check from the destination example (/p/multi-tenant-relational-data on the live URL, expect see the pattern fixture checks)
• data or object counts and checksums match the source.

Limitations

• Documentation only: nothing is executed automatically and no execution binding is offered.
• The source-side procedure is documented from Self-managed PostgreSQL's standard tooling and was not executed in this catalog's evidence; the destination side was verified with the pattern fixture.
• No full source-product parity is claimed: Custom extensions, tablespaces, replication topology, superuser-only settings and OS-level backups have no equivalent on the managed database.
• Verified on the node-22 template at s-1vcpu-1gb; region, compliance and request-duration limits are unknown.
• Managed PostgreSQL 16 only; extensions, connection limits and backup or restore procedures on the managed side are not verified beyond the pattern checks.

Cost estimate

Estimated 10.00 USD per month (size prices from pricing.toml at build revision a1b8c38919e59cd035ebabaced73cf84ece24371).

• app server x1 s-1vcpu-1gb: 5.00 USD
• managed PostgreSQL database x1 s-1vcpu-1gb: 5.00 USD

Destination always-on monthly price of the tested sizes; apps auto-pause when idle. Source costs are unknown to Ample.

Verification evidence

• canary_run on 2026-09-21T02:34:39Z at revision 1d28ae0-dirty (CLI 0.1.21): Destination side verified: the Express pattern fixture deployed on Ample (npm install, npm run build --if-present, npm run start on the node-22 template) and its checks passed (a tenant column on every row and query, with a cross-tenant read returning nothing (tenant_isolation=ok)). The source-side export from Self-managed PostgreSQL is documented from the vendor's standard tooling and was not executed by this catalog's evidence. (expires 2027-03-20T02:34:39Z)

Last verified: 2026-09-21T02:34:39Z

Execution binding

No execution binding. This recipe is documentation only; nothing is executed automatically.